from xml.etree.ElementTree import ElementTree,Element


def read_xml(in_path):
  '''读取并解析xml文件
    in_path: xml路径
    return: ElementTree'''
  tree = ElementTree()
  tree.parse(in_path)
  return tree

def write_xml(tree, out_path):
  '''将xml文件写出
    tree: xml树
    out_path: 写出路径'''
  tree.write(out_path, encoding="utf-8",xml_declaration=False)

def if_match(node, kv_map):
  '''判断某个节点是否包含所有传入参数属性
    node: 节点
    kv_map: 属性及属性值组成的map'''
  for key in kv_map:
    if node.get(key) != kv_map.get(key):
      return False
  return True

#---------------search -----
def find_nodes(tree, path):
  '''查找某个路径匹配的所有节点
    tree: xml树
    path: 节点路径'''
  return tree.findall(path)

def get_node_by_keyvalue(nodelist, kv_map):
  '''根据属性及属性值定位符合的节点，返回节点
    nodelist: 节点列表
    kv_map: 匹配属性及属性值map'''
  result_nodes = []
  for node in nodelist:
    if if_match(node, kv_map):
      result_nodes.append(node)
  return result_nodes

#---------------change -----
def change_node_properties(nodelist, kv_map, is_delete=False):
  '''修改/增加 /删除 节点的属性及属性值
    nodelist: 节点列表
    kv_map:属性及属性值map'''
  for node in nodelist:
    for key in kv_map:
      if is_delete:
        if key in node.attrib:
          del node.attrib[key]
      else:
        node.set(key, kv_map.get(key))

def change_node_text(nodelist, text, is_add=False, is_delete=False):
  '''改变/增加/删除一个节点的文本
    nodelist:节点列表
    text : 更新后的文本'''
  for node in nodelist:
    if is_add:
      node.text += text
    elif is_delete:
      node.text = ""
    else:
      node.text = text

def create_node(tag, property_map, content):
  '''新造一个节点
    tag:节点标签
    property_map:属性及属性值map
    content: 节点闭合标签里的文本内容
    return 新节点'''
  element = Element(tag, property_map)
  element.text = content
  return element

def add_child_node(nodelist, element):
  '''给一个节点添加子节点
    nodelist: 节点列表
    element: 子节点'''
  for node in nodelist:
    node.append(element)

def del_node_by_tagkeyvalue(nodelist, tag, kv_map):
  '''同过属性及属性值定位一个节点，并删除之
    nodelist: 父节点列表
    tag:子节点标签
    kv_map: 属性及属性值列表'''
  for parent_node in nodelist:
    children = parent_node.getchildren()
    for child in children:
      if child.tag == tag and if_match(child, kv_map):
        parent_node.remove(child)

def indent(elem, level=0):
    i = "\n" + level*"\t"
    if len(elem):
        if not elem.text or not elem.text.strip():
            elem.text = i + "\t"
        if not elem.tail or not elem.tail.strip():
            elem.tail = i
        for elem in elem:
            indent(elem, level+1)
        if not elem.tail or not elem.tail.strip():
            elem.tail = i
    else:
        if level and (not elem.tail or not elem.tail.strip()):
            elem.tail = i